The unpredictability that helped make Morgan a comedy force on multiple stages rises to a new, serious level this weekend when he hosts "Saturday Night Live," in his first major TV gig since suffering brain trauma and broken bones. The only safe prognostication is that fans will be rooting for him.

The 46-year-old entertainer's "SNL" return (alongside musical guest Demi Lovato) marks the latest step in a long, public comeback since a tractor trailer slammed into his vehicle on the New Jersey Turnpike, killing his friend and fellow comedian James McNair. Dire reports about Morgan's mortality gave way to sobering pictures of him as he began physical rehab.

Morgan’s injuries forced him to skip the "SNL" 40th anniversary special in February. Four months later, in an emotional interview with Matt Lauer on "Today," an at-times repetitive and weepy Morgan vowed: “I'll get back to making you laugh, I promise you.”

He'll get his chance Saturday at 30 Rockefeller Center, where he started on "SNL" nearly 20 years ago, creating characters like boisterous, animal-loving TV host Brian Fellows and developing the persona framework for Tracy Jordan, the comic he'd later play on Tina Fey's sitcom, "30 Rock."

In previews for his “SNL” homecoming, Morgan joked about his injuries, suggesting that in keeping with his past approach to comedy, nothing is off-limits. "Did I used to work here?" he quipped during an exchange with cast member Bobby Moynihan.

The bit underscored a quality that made fans embrace Morgan, long before the 2014 accident: Anything can happen when he goes "live from New York." The comic’s remarkable recovery hopefully will extend to the familiar “SNL” stage as he caps his battle through a personal hell, determined to make good on a promise to himself as much as to his audience.